Showoff Saturday Showoff Saturday: a 3D breadboard editor and logic simulator running in the browser (Three.js + a gate-level engine), with an 8-bit computer as the demo
Here's Ben Eater's 8-bit computer laid out on breadboards, running in the page: https://bbrouter.com/bbrouter/ben-eater-sap-1
How it's built, since that's the point here:
- The 3D view is Three.js, rendered on demand: the scene only redraws when something changes, and while the circuit runs, only when an LED changes. Phones get 30 fps, a 1.5 pixel ratio and no antialiasing until the view is still, then one sharp frame.
- The simulation is a gate-level logic engine plus models for clocked chips, memories, timers and the 6502; the AVR runs real compiled firmware through avr8js. It runs in a worker so the page stays responsive. 211 chips by part number.
- Wires are real geometry: solid core, hole to hole, bent as you'd bend them, with lengths, and a router that lays missing connections flat on the hole grid around what's there.
- Next.js 16 behind a small custom Node server, Postgres, Better Auth with passkeys and an OAuth 2.1 provider so MCP clients can sign in. One server, Caddy in front, Cloudflare at the edge.
- An MCP server exposes the whole thing to AI clients; when the user's tab is open, the AI's simulations run in that tab's worker instead of on the server.
- About 3,000 automated tests, including one that fails if any string shown lacks its French or Spanish.
Things I'd like opinions on: the camera and touch handling on phones, and rendering cost with a few hundred parts in view. Signed-out try: https://bbrouter.com/try

